Haematoma is a localised collection of blood, usually clotted, in an organ, space or tissue, due to a break in the wall of a blood vessel. It may be classified according to the degree affected. It may be petechiae, purpura, or ecchymosis.

A petechia is an initially purplish red spot that eventually turns blue or yellow. It is caused by a small intradermal or submucous hemorrhage. It has a diameter of 1 to 2 mm, or basically less than 3 mm, making it smaller than ecchymoses or purpura.

The petechiae are very small, perfectly rounded spot on the body surface like skin. The most common cause is physical trauma, such as coughing, vomiting or crying that may lead to formation of petechiae in the face, especially around the eyes. In other cases, petechiae can be a sign of thrombocytopenia or clotting factor deficiencies.